add linting for shell scripts and Dockerfiles

* add hadolint for dockerfile linting
* add hadofile config
* add checks for dockerfiles and shellcheck into makefile
* shellcheck fixes
* add workaround so that .env can be sourced again from version.sh
* hadolint fixes
* print progress of build/run.sh
* fix check for jq in setup.sh

relates to #41 and #26

zpush/Dockerfile

@@ -20,6 +20,8 @@ ENV KOPANO_ZPUSH_VERSION=$KOPANO_ZPUSH_VERSION
 ARG RELEASE_KEY_DOWNLOAD=0
 ENV RELEASE_KEY_DOWNLOAD=$RELEASE_KEY_DOWNLOAD
 
+SHELL ["/bin/bash", "-o", "pipefail", "-c"]
+
 # install Kopano WebApp and refresh ca-certificates
 RUN \
     # community download and package as apt source repository

zpush/start.sh

@@ -7,10 +7,11 @@ ADDITIONAL_KOPANO_PACKAGES=${ADDITIONAL_KOPANO_PACKAGES:-""}
 
 set -eu # unset variables are errors & non-zero return values exit the whole script
 
-[ ! -z "$ADDITIONAL_KOPANO_PACKAGES" ] && apt update
-[ ! -z "$ADDITIONAL_KOPANO_PACKAGES" ] && for installpkg in "$ADDITIONAL_KOPANO_PACKAGES"; do
-	if [ $(dpkg-query -W -f='${Status}' $installpkg 2>/dev/null | grep -c "ok installed") -eq 0 ]; then
-		apt --assume-yes install $installpkg;
+[ -n "${ADDITIONAL_KOPANO_PACKAGES// }" ] && apt update
+[ -n "${ADDITIONAL_KOPANO_PACKAGES// }" ] && for installpkg in $ADDITIONAL_KOPANO_PACKAGES; do
+	# shellcheck disable=SC2016 disable=SC2086
+	if [ "$(dpkg-query -W -f='${Status}' $installpkg 2>/dev/null | grep -c 'ok installed')" -eq 0 ]; then
+		apt --assume-yes install "$installpkg"
 	fi
 done
 
@@ -42,6 +43,7 @@ tail --pid=$$ -F --lines=0 -q /var/log/z-push/z-push-error.log &
 echo "Starting Apache"
 rm -f /run/apache2/apache2.pid
 set +u
+# shellcheck disable=SC1091
 source /etc/apache2/envvars
 # cleaning up env variables
 unset "${!KCCONF_@}"